The present invention relates in general to gas tight respirator receptacles and, in particular, to a new and useful gas tight receptacle for an emergency respirator which includes a lock for preventing inadvertent or undesired opening and leakage of the receptacle.
In underground operations, such as in mines, where conditions may be rough, it will happen that the closures of emergency or readiness receptacles of emergency respirators, carried by persons for self-protection, are inadvertently opened after destruction of a lead seal used in the receptacles. Depending on the kind of receptacle, this could become dangerous for the function of the respirator which is packed in the readiness receptacle only if the receptacle is then opened by removal of its cover. In these cases there would then be no assurance that the equipment parts of the respirator, such as the breathing bag, the mouthpiece, and also the hose, etc., would not be damaged also. Such leakage may cause excessive water absorption which too would damage the respirator. If it were possible to hold the cover even with the closure open, at least on the bottom part of the receptacle, if not tightly, at least partly, then reclosing the readiness receptacle would be possible without extensive damage of the respirator and its sensitive parts.
In a known air tight readiness receptacle for emergency respirators, which also consists of two parts, namely a bottom part and a cover, these parts are pressed one on the other with closure means under adjustable contact pressure. At least one bayonet type lock serves as closure means. An oblong slotway, of the lock, disposed in one receptacle part, is inclined and has a serration on the upper inner side thereof. The tip of a bayonet pin engages into the serration. The pin is disposed on the other receptacle part. The bayonet pin, which rotatably passes through the receptacle wall, terminates on the outside of this receptacle part as a crank type operating lever. By the latter, the relative contact pressure of the receptacle parts, separated from each other by seals, is selected by rotation. The operating lever is then fixed in its end position by a lead seal. The soldering of the operating lever in the bushing in the receptacle wall, which here serves primarily for sealing, is at the same time an additional safety against unintentional opening of the emergency or readiness receptacle. This would here mean removal of the cover from the bottom part.
A disadvantage in this design is the extremely great expense of construction, which moreover demands for its function, a possibility of neat engagement of the gear in the serration over the entire path. For the unskilled user, the correct operation of the closure means is difficult to carry out, especially in a situation of possible danger. The receptacle can be opened completely by removal of one receptacle part, e.g. the cover, only after the gear is out of engagement after a full rotation of the operating lever. Yet the user is able to remove the cover unnoticed by the equipment personnel, and also to place it on again. The respirator may then have suffered some damage already. (West German Pat. No. 12 28 145).